bear - ingn.1 the manner in which one comports oneself; 2 the act, power, or time of bringing forth offspring or fruit; 3 a machine part in which another part turns [a journal ~]; 4pl. comprehension of one's position, environment, or situation; 5 the act of moving while supporting the weight of something [the ~ of the cross].

All the other lots in the neighborhood are also nonconforming, because they were created before the current minimum lot size went into effect.

Nonconforming properties are not the same as "illegal properties." A great deal of properties in Minneapolis are nonconforming, because the zoning changes all the time.

Just because a property is nonconforming doesn't mean you can't sell it (without an issue) or live in it.

They do create an issue for new building permits. You have to get a variance from the city to pull a permit for creating anything that is new that will not conform to the zoning code.

We had to do that in 2005 when we split the lot we owned from 9600 square feet to 4800 square feet -- even though all the neighboring lots are also 4800 square feet, we had to get a variance to create two new lots < 5000 square feet each. (We built our current house in 2006 on one of the two smaller lots, and sold the other lot along with the house we lived in previously.)

We do not have a variance for the minimum floor area ratio on our lot.

In R1A at this time no building permit will be issued without a variance for a new multifamily dwelling (even though the neighborhood is full of duplexes).

Similarly, no building permit will be issued for a new dwelling that would have a habitable floor area > 0.5 (lot area).

And no building permit will be issued without a variance for any construction that will expand the habitable floor area past the minimum floor area ratio. So our home is limited to 2400 square feet habitable space, even though many pre-existing homes don't conform to this and can legally be sold with no trouble.

In the past few years the rules were stringently tightened up for awarding variances.

If we were trying to get the same variance we got in 2005 to split our old double lot today, we probably would not be allowed to, and building the house we own would not be possible.

Obviously it is possible to finish the basement on our own without pulling a permit and thereby coming to the city's attention.